Method for operating optical sensors

Abstract

A method for operating an optical sensor for measuring a physical quantity with a defined scale value that is subject to a calibration certification. The measurement accuracy of the quantity being measured is dependent on at least one external condition, and a given scale value is used for the measurement according to the desired measurement accuracy. The scale value is appropriately changed when the measurement accuracy changes due to a change of external condition. An optoelectronic sensor has a switching arrangement for changing the scale value. The sensor is more diversified and can cover larger measurement ranges without requiring new certifications or authorizations for the different measurement ranges.

Description

BACKGROUND OF THE INVENTION[0001]The invention concerns a method for operating an optical sensor for measuring a physical quantity, as well as the corresponding sensor.[0002]In general, one must define a so-called scale value for measurement devices with which a physical parameter is being measured and which operate pursuant to a calibration certificate. The scale value corresponds to the smallest indicated dimensional unit and is used to define the measurement accuracy. The measurement results may only be indicated in multiples of the scale value. By definition, scale values should only be selected in steps of 1, 2 and 5 times 10n (n is an integer). The definition is mandated by national authorities, for example, in Germany, by the Physikalisch Technische Bundesanstalt, which follow the recommendations of the OIML (International Organization of Legal Metrology).[0003]Each calibrated measurement device has one of these scale values and is suitable for applications with a measurement...

AI Technical Summary

Benefits of technology

[0005]Based on this state of the art, it is an object of the invention to provide an improved method and sensor which are more diversified and can cover larger measurement ranges.

[0007]In this way, a large measurement range can be covered by a single sensor. The use of different sensors for different conveyance speeds, for example, is no longer necessary.

[0013]Especially when the external condition is detected automatically, it is advantageous that the scale value is also switched automatically as a function of the external condition, for then no manual intervention is required and the entire measurement process occurs automatically with the desired measurement accuracy.

Problems solved by technology

A problem occurs when the measurement accuracy cannot be constant because it is influenced by external conditions.

Thus, the measurement layout at the conveyor either has a limited range of application or it must have several sensors with different scale values, which is correspondingly expensive and cumbersome.

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